1. Field of Invention
This invention relates generally to a propulsion mechanism for use with float tubes (aka. xe2x80x9cbelly boatsxe2x80x9d), pontoon boats, and other float devices commonly used in fishing, duck hunting, and other aquatic pursuits and, more particularly, to a foot fin assembly for propelling the user of such devices. Specifically, the present invention relates to an improved universal foot fin assembly which is easily adaptable for use in propelling the user of a float tube or other float device in either a forwardly facing direction or a backwardly facing direction in water while simultaneously permitting the user of such foot fins to walk in a forwardly facing direction in shallow water and on land without removing the fin assembly.
2. Description of the Prior Art
In general, users of float tubes and similar aquatic apparatus use some type of propulsion aid on their feet to assist in moving about the water""s surface. Most float tube fins presently used are similar in design to the foot fins used by swimmers and divers. Illustrations of such fins include those shown in U.S. Pat. Nos. 3,183,529, 4,857,024, 4,929,206, 4,940,437 and 5,597,336. Such devices operate by movement of the user""s legs and feet in a flutter kick which propels an outstretched swimmer or diver in a forward direction. Conversely, they propel a person seated in or on a float tube or similar device rearwardly or backwardly relative to the direction he or she is facing. This backward movement is preferred by pontoon boat users on moving streams who need to face downstream and propel backwards to steer a course and avoid obstructions. However, still water float tube users generally desire to move forward when moving about on the water or casting to rising fish.
The forward extending fin blades of the previously described fins restrict foot movement, creating a risk of tripping and falling while walking with the fins on. Walking in marginal water to enter or exit a body of water is particularly hazardous, for in addition to the clumsiness of the protruding fins and the limitations of movement and visibility caused by the float tube the walker has to overcome the water""s resistance on the fins with each step. As a consequence, most users of forward extending fins walk backward to enter and exit the water. Walking and wading backward, especially without use of the arms and hands as a balancing aid (that use precluded by hand carrying the annular float tube in position about the lower torso) creates a significant danger of falling, injury and drowning. Strenuous backward kicking with such prior art fins tends to cause leg cramps and fatigue.
The process of donning and removing a round float tube while wearing such forwardly extending fins is also difficult and hazardous. For example, the bulk and shape of a float tube limits movement, necessitating that the fins are attached to the user""s feet prior to donning the float tube. In such an instance, with the float tube lying flat on the ground and the fins attached to the user""s feet, the user balances on one foot while stepping over the circumference of the tube with the other foot to insert that foot with fin into the leg opening of the float tube seat. Thus straddling the tube, the user then shifts his or her balance to the foot now inside the tube so as to lift the opposite foot with fin over the tube and insert it also into the leg opening of the seat. The forward extension of such prior art fins, their general configuration and size, and the constriction of the seat of an annular float tube makes it extremely awkward to insert both feet with fins in place into the leg opening of a float tube. Balancing is especially difficult while bending over to maneuver the unwieldy tube into position to facilitate inserting the forward extending fin of the second foot into the leg opening.
As the result of such difficulties, several fins have been developed to provide a means of forward propulsion by float tube users. Moreover, designs have been provided wherein a single paddle is secured to an existing shoe of a float tube user. Such designs include U.S. Pat. Nos. 2,395,844, 4,664,639 and 5,527,196. Other designs such as U.S. Pat. Nos. 2,276,082 and 3,432,868 have provided elongated or funnel shaped fins attached to the outside sides of the legs as an integral part of wading boots or waterproof garments for float fishing. A device known as the Paddle Pusher which is manufactured by Fishmaster Manufacturing Co. of Oklahoma City, Okla., provides side paddles to be worn on existing tennis shoes or other foot gear. The design of the previously described fins compel a float tube user to assume an unnatural forced vertical posture to propel the float tube on the water. Moreover, these designs are generally inefficient lacking the advantage of an extended longer arc of leg movement in the water which can be gained by positioning the fin in its operating position underneath the foot of a user. They also lack the advantage of a fin biased to an operating position from which the fin will generate usable thrust more rapidly than a fin which must be initially extended to its operating position by movement through the water. The design and construction of a float tube seat typically places a user thereof in the posture of a person seated in a chair with his or her legs and feet extended generally outwardly and forwardly. In such a position kicking is restricted to lower leg movement with the legs pivoting at the knees, not the hips as is assumed in many prior art devices.
Use of the fin disclosed in U.S. Pat. No. 4,664,639 in which the fin is integrally secured as part of the sole of the shoe or as part of a sleeve that fits over the shoe requires the user to lean forward against the designed posture of the float tube in order to position his or her body and legs in a generally upright vertical plane to provide a sufficient length of kick to make use of the device. This is due to the fact that the integral fin flap is by its nature biased toward its retracted position against the shoe sole necessitating unusual motion and force from the leg and foot of the float tube user to extend the fin away from the sole of the shoe and into position to create forward user motion. The devices of U.S. Pat. Nos. 2,276,082 and 3,432,868 and the Paddle Pusher also compel the user of a float tube to assume a forced, generally upright vertical position to move through the water. Much of the user""s leg motion with these devices is wasted, and such awkward movement within the float tube is inherently uncomfortable.
U.S. Pat. No. 6,077,139 provides a fin surface of coated fabric into which tubular ribs are sewn to stabilize the fabric in a generally planar fin surface. The device attaches loosely downwardly and behind the heel of the user""s foot, being secured to the user""s boot by woven straps and buckles. In walking to enter and exit the water the fin surface drags on the ground behind the user""s foot, thereby creating a danger of tripping and falling if the user of the device were to be in a rearward off balance position. In such an off balance position, the fin surface and its integral ribs would catch on the ground restricting or preventing a backward movement of the user""s foot to regain his or her balance thus causing the user to fall over backward. In use in water the fin hangs downwardly from its attaching straps, being biased toward an operating position only by the forces of gravity and an adjustment in fin width by the manner in which the heel straps are adjusted to the user""s foot. Because it is not positively biased to its open operating position the fin frequently does not fill with water in a kicking motion and thus is generally inefficient. Many users of float tube fins do not wear boots, preferring to eliminate the weight of the boot by using only xe2x80x9cstocking footxe2x80x9d waders. If used over stocking foot waders the device tends to slip off the foot since there is no protruding boot heel to retain the fin and its attachment straps. The maker of the device suggests that its position can be reversed on the user""s foot to propel backward for trolling or going backwards. Movement on land and wading to enter or exit a body of water with the fin in this reversed position would of necessity be restricted to walking backward as the forward facing fin member dangling loosely from the users ankle would catch on the ground if the user were to attempt to walk forward. In either direction the user must walk upon a portion of the tubular center rib, which is painful if wearing only stocking foot waders, and unstable if wearing boot foot waders.
The devices of my U.S. Pat. Nos. 5,531,621 and 5,645,460 overcome many of the objections to the prior art devices described above, although the hinging arrangement and means of extending the fins of these inventions can sometimes be a little awkward in moving them from the closed to operative positions. Both devices are rather complicated and expensive to manufacture. The device of my U.S. Pat. No. 5,593,333 improves the ease by which a user can move the device from its reset position for minimum water resistance to its operative position for paddling or to a fixed position for walking in shallow water. However, the hinging means and bias means for the device are heavy and expensive to manufacture. Maintaining free movement of the hinging requires special lubricant impregnated bushings and Salt water use presents a corrosion problem due to electrolytic activity of dissimilar metals used in the spring and hinge. The device of my U.S. Pat. No. 6,227,923overcomes most of the use and performance objections, although the stresses of walking upon the fin surface over rocks and other debris necessitates constructing the fin member of high quality durable material such as polyurethene. As with most premium materials, urethenes are quite expensive, requiring the fin to be priced at a rate considerably higher than the more popularly priced swim fins. Further, a need still exists for a pontoon boat fin for river fishermen which allows unrestricted forward walking and wading while also propelling the user in a backward direction on the water.
Accordingly, it is one object of the present invention to provide an improved universal float tube fin that is simpler, lighter, more efficient and less costly to manufacture which allows a user to walk forward on land and in shallow water and which can be selectively assembled to enable a float tube user to propel either forward or backward on water.
It is another object to provide a more durable improved float tube fin having fewer separate moving parts requiring less maintenance and reducing the potential for lost or broken parts.
An additional object is to provide a fin assembly of a design which does not require special release mechanisms to prevent injury to the user which could occur by the fin becoming entangled in mud or debris.
To achieve the foregoing and other objects and advantages which will become apparent from a consideration of the ensuing description and drawings in accordance with the purpose of the present invention as embodied and broadly described herein, an improved fin assembly in three separate distinct embxxlinets is disclosed for attachment to the foot, foot covering, or boot of a float tube or pontoon boat user (or the user of a similar device) . . .
In the first of two preferred embodiments fin members and unique wading boots are provided in which the fin members can be removably selectively attached to mounting and latch fixtures which are molded integral as part of the wading boots, the mounting of the fin members to the fixtures providing an articulated coupling which allows the fin members to be selectively retained in a first retracted position wherein the fin member is positioned above the sole of the user""s boot to enable the user to walk upon a surface without removing the fin members or in a second extended operating position below the sole of the user""s boot for propelling the user in the water. The fin members of the first preferred embodiment can also be selectively removed from the wading boots for conventional use of the waders.
In the second preferred embodiment similar fin members are provided as part of a kit which also includes separate mounting and latch fixtures to be permanently affixed to conventional wading boots by cementing, vulcanizing, or other known permanent attachment means in such manner that the fin members of the second embodiment (which can be selectively attached to the mounted fixtures permanently affixed to the user""s boot) can also be selectively removed for conventional use of the waders without the fin member being attached to them.
In a third preferred embodiment similar fin members are removably selectively attached to mounting and latch fixtures which are molded as integral parts of a base member which can be removably attached to conventional wading boots or over stocking foot waders or other foot gear of the user. In this embodiment a separate retracted position latch member may be provided to be permanently or removably attached to the user""s waders, legs, or covering thereof . . . the boot or foot covering having a sole, toe, ankle, and heel portions. The assembly includes a fin member having a front end portion, a rear end portion, an upper surface, a lower surface, and right and left sides. The fin member is connected to a removable, permanently attachable, or permanently installed mounting means for releasably attaching the fin member to the boot or foot covering of a float tube user. The mounting means further provides an articulated coupling of the fin member which allows the fin member while the fin assembly is attached to the user""s foot to be selectively retained in a first retracted position wherein the fin member is positioned above the sole of the user""s boot to enable the user to walk upon a surface without removing the fin member or fin assembly or to be selectively pivoted to and retained in a second base operating position wherein the fin member is positioned below the user""s boot sole for use in propelling the user in the water. Flexure characteristics of the composition of the fin member material, the limiting configuration in which it is constructed, and an integral hinge means allow the fin member to establish a first fully extended operating position in a power kick in which the flexure of the fin member is limited from exceeding the optimum position for maximum resistance to the flow of water against its upper surface when the fin member is moved through the water with the fin member upper surface leading into the direction of movement against the water thereby propelling the user in the opposite direction. In a second return operating position in which the lower surface of the fin member is moved leading into the water the fin member feathers in response to pressure of water flowing against the lower surface, freely pivoting on the base member mounting studs until contact of latch structures formed in the extending sides of the fin member and on the sides of the base member or boot restrict further travel. Having been retained by the latch means the fin member then continues to feather, flexing at a hinge point established by apertures in the fin surface adjacent to cleavages in stiffening ribs which are formed integral with the underneath surface of the fin member to the limiting characteristics of the material from which the fin member is constructed offset by the pressure of water against the fin member lower surface. When so feathered in the return operating position the plane of the rear portion of the fin member is generally more closely parallel to the plane of the sole of the users boot than when the fin member is freely positioned in its base operating position. In the feathered return operating position the fin offers minimal drag or resistance to the flow of water against its lower surface.